1. Field of the Invention
The present invention relates to a control system for a adjustable damping force damper, which controls variably an adjustable damping force of a damper provided to a suspension apparatus of a vehicle in response to a moving condition of the vehicle.
2. Description of the Background Art
In Japanese Patent Unexamined Publication No. JP-A-60-113711, the adjustable damping force damper in which MRF (Magneto-Rheological Fluids), whose viscosity is changed by applying a magnetic field, is employed as a viscous fluid of the adjustable damping force damper for the suspension apparatus and also a coil used to apply the magnetic field to the magneto-rheological fluids in the fluid passage is provided to a piston, which is slidably fitted into a cylinder, is known. According to this adjustable damping force damper, an damping force of this damper can be controlled arbitrarily by changing a viscosity of the magneto-rheological fluids in the fluid passage by applying the magnetic field generated by supplying an electric current to the coil.
In Japanese Patent Unexamined Publication No. JP-A-07-237420, in order to improve a ride performance when a vehicle comes down from steps, the control system for prohibiting a control that increases an damping force of the damper when a downward acceleration is detected is known.
By the way, in the case where the vehicle to which the skyhook control is applied gets over steps on a road surface, the passenger's feeling is different between in a case where the vehicle goes up onto the steps and in a case where the vehicle comes down from the steps. Therefore, when a gain of the skyhook control is set uniformly in both situations, there are undesirable possibilities that the passenger may feel uncomfortable and a ride performance may be deteriorated.